Levonorgestrel: How It Works and When to Use It

Here’s the quick truth: levonorgestrel is a progestin used both as a morning-after pill and inside some IUDs. As an emergency pill it can lower the chance of pregnancy after unprotected sex, and as a levonorgestrel-releasing IUD it provides long-term birth control.

Emergency pill — what to expect and how to take it

The common dose is 1.5 mg taken as a single tablet (or two 0.75 mg tablets 12 hours apart). Take it as soon as possible after unprotected sex — it works best within 72 hours and effectiveness falls the longer you wait. It mainly delays or prevents ovulation and thickens cervical mucus so sperm can’t reach an egg. It won’t work if you’re already pregnant and it won’t interrupt an established pregnancy.

If you vomit within two hours of taking the pill, take another dose. If your period is more than a week late after taking the pill, get a pregnancy test. Emergency levonorgestrel does not protect against STIs and is not meant as regular contraception.

Levonorgestrel IUDs and long-term use

Levonorgestrel IUDs (brands like Mirena, Kyleena) release small amounts of hormone into the uterus. They’re over 99% effective for ongoing contraception and can reduce heavy periods. Some clinicians will offer an IUD as emergency contraception if inserted within five days after unprotected sex — this is a highly reliable option, often more effective than pills.

Side effects are usually short-term with the emergency pill: nausea, fatigue, breast tenderness, or spotting. With an IUD you may have irregular bleeding at first, cramping during insertion, and rare risks like expulsion or infection. If you have severe abdominal pain, fever, or heavy bleeding after an IUD insertion, see a clinician right away.

Certain drugs lower levonorgestrel’s effectiveness — enzyme inducers like rifampicin, some anti-seizure meds, and St. John’s wort. Body weight also matters: evidence suggests reduced pill effectiveness in people with BMI over 30; in those cases a copper IUD or ulipristal acetate (Ella) are better emergency options when available.

Practical buying tips: levonorgestrel emergency pills are available over the counter in many countries. If you order online, use a licensed pharmacy, check product labels, and avoid unusually cheap or unbranded tablets. Keep a pack on hand if you might need it, but don’t use emergency pills as routine birth control — talk to your provider about a regular method that suits you.

After using levonorgestrel, start or resume your regular contraception as advised by your clinician. If you’re unsure what to choose, ask for a quick clinic visit — they can discuss options, check for pregnancy, and offer an IUD if that’s right for you.

Drospirenone vs. Levonorgestrel: Which is Right for You?

In today's blog post, we'll be discussing the differences between Drospirenone and Levonorgestrel, two commonly prescribed birth control hormones. We'll delve into their unique properties and potential side effects in order to help you decide which option might be best for you. It's important to note that everyone's body reacts differently to medications, so it's always a good idea to consult with your healthcare provider before making any decisions. Stay tuned for an informative comparison that will hopefully make your choice a bit easier. Remember, finding the right birth control is a personal journey, and there's no one-size-fits-all solution!